rockets bp

8/9/2019 Rockets BP

1/33

Universal Hybrid Rocket Tool

- 1 -

PASSFIRE FORUM

SUMMARY OF STEVE LA DUKECOMMENTS

8/9/2019 Rockets BP

2/33


- 2 -

SECURITY ...................................................................................................................................................... 4

BLACK POWDER ROCKETS ..................................................................................................................... 6

MAKING BLACK POWDER R OCKETS ............................................................................................................. 6 R ICING BLACK POWDER - HOW MUCH SOLVENT ? ........................................................................................ 6 DELAY AND TAIL FOR ROCKETS .................................................................................................................... 6

CHRYSANTHEMUM OF MYSTERY NEED MORE SULFUR , IF YOU DON’T USE WILLOW CHARCOAL ................. 7 MAKING WHISTLE MIX ........................................ ........................................... .......................................... 8

WHISTLE ROCKET FUELS ............................................................................................................................... 8 HOW TO DO ? ................................................................................................................................................. 8 VASOLINE TO REDUCE SENSITIVITY .............................................................................................................. 9 CATALYST ..................................................................................................................................................... 9 DIFFERENCE BETWEEN SALYCLATE AND BENZOATE WHISTLE ..................................................................... 9 OTHERS ........................................................................................................................................................ 10

HYBRID ROCKET USING THE UNIVERSAL HYBRID SPINDLE ........................................ ............ 11

I NTRODUCTION ............................................................................................................................................ 11 HYBRID # 1 MIX ........................................................................................................................................... 11

HYBRID # 2 MIX ........................................................................................................................................... 12 FLIGHT PREFORMANCE OF THE HYBRID R OCKET ....................................................................................... 13 HYBRID ROCKET TOOLING DIMENSIONS ...................................................................................................... 13

3/4” WHISTLE ASSISTED COLORED TAILED ROCKET .................................................................. 14

WHISTLE ROCKET FUELS ............................................................................................................................. 14 MAKING WHISTLE ASSISTED COLORED TAILED ROCKET ............................................................................. 14

LONG WINDED SCREAMER ROCKET .............................................................................. ................... 15

WHISTLE ROCKET FUELS ............................................................................................................................. 15 MAKING LONG WINDED SCREAMER R OCKETS (LWS) ............................................................................... 15 PRESSING LONG WINDED SCREAMER R OCKETS (LWS) ............................................................................. 15 BETTER SCREAMING .................................................................................................................................... 15

FLIGHT TIME ................................................................................................................................................ 16 ENDBURNING ROCKET ........................................................................................................................... 17

MAKING ENDBURNING ROCKETS USING HYBRID MIX # 2 ........................................................................... 17 TO INCREASE THE POWER OF END BURNING ROCKETS, ADD WHISTLE MIX (HYBRID #2) ............................ 17 THE ENDBURN ROCKET I WON COMPETITION .............................................................................................. 18 E NDBURNING ROCKET MADE FROM COMMERCIAL BLACK POWDER ........................................................... 18 NEW E NGLAND PAPER TUBES ..................................................................................................................... 18 NOZZLE DIAMETERS FOR ENDBURN ROCKETS ............................................................................................. 18 NOZZLE EROSION ........................................................................................................................................ 19

STINGER MISSILE ..................................................................................................................................... 20

MAKING STINGER MISSILE USING HYBRID MIX # 2 ...................................................................................... 20

MAKING STINGER MISSILE USING WHISTLE MIX #2 ..................................................................................... 20 STROBE ROCKET....................................................................................................................................... 21

MAKING STROBE ROCKETS .......................................................................................................................... 21 PREPARING STROBE MIX .............................................................................................................................. 21 NC SOLUTION .............................................................................................................................................. 21 STROBE ROCKET MIX - STROBE RATE .......................................................................................................... 22 I NCREASE THE STROBE PULSES PER SECOND ............................................................................................... 22 STROBE ROCKET MIX - SENSITIVITY OF FORMULA ...................................................................................... 22 PRESSING STROBE MIX - DANGER ................................................................................................................ 22 STORE STROBE ROCKETS ............................................................................................................................. 23

8/9/2019 Rockets BP

3/33


- 3 -

PRESSING ROCKETS ...................................... ........................................ ........................................... ........ 24

HOSE CLAMPS ON SLEEVE ............................................................................................................................ 24 BP LOADING PRESSURE................................................................................................................................ 24 YOU NEED LESS PRESSURE FORCE FOR THE FIRST INCREMENTS .................................................................. 24 PRESSURE FORCE GAUGE CONVERTER ....................................................................................................... 24 THE TUBE WALL STRETCHES AND THE PAPER TEARS APART FROM HIGH LOADING PRESSURE. .................. 25 I NCREMENTS ................................................................................................................................................ 25

TO LARGE I NCREMENTS ............................................................................................................................... 25 SPACERS TO REDUCE TRAVEL OF THE HYDRAULIC PRESS ........................................................................... 25 MISALIGNMENT IN THE PRESS ..................................................................................................................... 26 R EMOVE AN JAMMED RAMMER ................................................................................................................... 26

ROCKET ENGINE CASINGS .................................................................................................................... 27

MOTOR CASINGS SOAKED IN WOOD HARDNER ............................................................................................ 27 TUBE LOADING PRESSURE TEST ................................................................................................................... 27 A GOOD, STRONG, HARD WOUND TUBE WITH A THIN WALL IS BETTER THAN A THICK WALLED , SOFTERWOUND TUBE ............................................................................................................................................... 27 A THICK WALLED TUBE ISN'T REQUIRED WHEN USING THE NEW E NGLAND TUBE ..................................... . 28

OTHERS ........................................................................................................................................................ 29

N.C. LAQUER ............................................................................................................................................... 29 MINERAL OIL IN BP R OCKETS WILL REDUCE THE THRUST SINIFICANTLY .......................................... ........ 29 MAKE CHARCOAL FROM SHAVINGS TO ELIMINATE THE GRINDING STEP .......................................... ........ 29 BALSA WOOD TO MAKE R OCKET STICKS .................................................................................................... 29 STICKS FOR R OCKETS .................................................................................................................................. 29 FINS FOR ROCKETS ....................................................................................................................................... 30 FUSING ROCKETS ......................................................................................................................................... 30 LAUNCHING ROCKETS.................................................................................................................................. 30 DELAY FUSE ................................................................................................................................................. 31 STAGED ROCKETS ........................................................................................................................................ 31 NOZZLE ........................................................................................................................................................ 31 TO LIGHT PAYLOAD ..................................................................................................................................... 32 4" AND 5" SHELL MAKING ............................................................................................................................ 33

8/9/2019 Rockets BP

4/33


- 4 -

SECURITY

PROTECT YOURSELF

To protect yourself when making this mix, I wear a protective face shield and leather gloves. Atleast if it does blow up in your face, you won't have the bare flame licking you in the face. Any kindof cotton sweat shirt or long sleeve jacket will protect your arms. And use common sence. Fromthis I think there are some take home messages:

1. Wear a heavy glove and safety glasses or face shield when pounding rockets. If it blows upyour hand is what will be the most damaged. Do wearing only leather gloves and not nitrilgloves, because they will burn.

2. Prevent static ignition: Make sure you ground everything in your work area, includingyourself.

3. Never pound whistle and strobe mix ! Even pounding black powder rockets is dangerous.Do never pound any composition that contain titanium or any other sparking ingredients.Rockets should be pressed behind a bullet proof shield.

4. Always, always check the fit of each rammer before you start ramming to make sure wherethey jam onto the spindle. Then mark this point on the rammer to show where this point isand don't go beyond it.

5. Always look into the rammers before each use and check to see if any fuel is built upinside. This reduces the size of the hole and it will jam on the spindle before it reaches theline scribed on the rammer.

6. When you change fuels, especially when going from pressing whistle rockets to poundingblack powder, make sure you clean out the bores of the rammers throughly before youbegin your next project.

7. Keep your tooling in complete sets in their own containers. If you have more than one set oftooling of the same diameter, perhaps you should mark the tooling itself as well.

8. If you use a universal tool set with whistle fuel, then perhaps you should dedicate thattooling to pressing only.

9. If you press whistle or strobe mix, then don't let the pressure well on the mix. Release itimmediately.

10. If you are building in an unfamiliar place, then do things in slow motion because you'remore likely to make a mistake.

11. Be extra careful when you are teaching someone how to do things. Being safe is moreimportant than your student knowing what the hell you're talking about.

12. Adding titanium to the mix while pressing, makes the operation much more sensitive toignition. And anybody that uses sponge titanium in they're fuel for pressing is just makingthe sensitivity much more prone to ignition. I would never use sponge titanium in any mixesthat I press. I never press whistle rockets with titanium in the core, I do use it in the delayportion of the rocket.

13. Vasoline reduce sensitivity of whistle mix. It's safer to press pyrotechnic fuels if vasoline ispresent in the mix. So be careful to press whistle mix without vasoline.

14. NC lacquer makes makes any mix much more sensitive to ignition.

15. Strobe mix is the most sensitive mix . It is a very sensitive mix to both shock and friction.

16. Check each flight stick you've made and bend it slightly in all directions and check for aweak spot. If there is one, it will break. Better to break in your hand that in the air 50 feetup.

8/9/2019 Rockets BP

5/33


- 5 -

ALWAYS M ARK AND CLEAN R AMMERS

What I think happened was that there was a trace of whistle fuel inside the rammer, and when Jeffput that final blow to the rammer with the hammer, it ignighted. This wasn't the worst of theproblem. Since the rammer bottomed out on the spindle before it got tight on the spindle, there wasdirect metal to metal contact. This was a very unfortunate event, but it caught somebody who didn'tcheck the rammer fit with the spindle before he started ramming. All I can say at this point is Jeffviolated one of the most important rules when you start to make rockets.

1. Always, always check the fit of each rammer before you start ramming to make sure wherethey jam onto the spindle. Then mark this point on the rammer to show where this point isand don't go beyond it. Once you begin to collect different spindles, along with theirrammers, it becomes more of a concern to keep them separated. I don't permantly markthem, but always mark them with a sharpy or place a piece of tape at the jam point rightbefore I start to press. I do this every time with each motor, then remove any rammers andplace them someplace else. This is a ritual with every motor I go through. It's part of thenecessary process to stay safe.

2. Another point to consider when using your tooling to make different rockets. When youchange fuels, especially when going from pressing whistle rockets to pounding blackpowder, make sure you clean out the bores of the rammers throughly before you begin yournext project.

So, in a nut shell, make sure you know the jam point of each rammer before you begin ramming orpressing. After you finish using a rammer, clean it out throughly before you begin using the nextrammer, then place that rammer at least one step away from you, then grab the next rammer thatis at least one step in the other direction. Leave the proper rammer inside the rocket before youleave the scene, and remember where you are after you come back. When I get back, I make athorough inspection of the process before I begin.

USE TITANIUM ONLY IN THE DELAY - NEVER USE SPONGE TITANIUM

I never mix sponge titanium with it either or press sponge titanium with whistle mix. I only useatomized or flake titanium. Why? Would you press whistle mix with a hand full of gravel thrown in ?

A titanium to titanium shear could have caused the heat that caused the ignition. Some how, Ibelieve this is the culprit. When I press the fuel increment in a motor, I bring up the pressure very

quickly and release it immediately. I even take a slight moment before I reach around the blastshield to grab my motor to add the next increment, after the pressing operation. So adding titaniumto the mix while pressing, in my opinion, makes the operation much more sensitive to ignition, andthat's why I only do it in the solid portion above the spindle in my motors. And anybody that usessponge titanium in they're fuel for pressing is just making the sensitivity much more prone toignition. I would never use sponge titanium in any mixes that I press. This would be like addinggravel to the whistle mix while pressing. Why have I been so lucky for the past 17 years ?

OTHERS

And the dangers of static ignition are present more in the winter time than in the summer. I don'teven make whistle mix anymore in the winter.

If I used an electric mixer for all the whistle mix I've made since 1991, I would't be here now on this

site. The kitchen mixer I use is a hand held device with no moving parts, no electricty involved. It'sa pie crust doe mixer with metal teeth and a handle to incorparate the chems together. Go to MagicChef web site and search for pastery mixer.

When I first started making whistle mix, without a catalyst and without vasoline, I used to bind itwith NC lacquer. Give this mix a friction test and an impact test and see for yourself. It doesexplode and ignite. Now, for anybody that wants to make whistle mix without vasoline, fine. I thinkit's a little more sensitive without it.

And one more thing. With all the rockets I've made for the past 44 years I've been making them, Inever had one blow during construction. Thank God and good common sense.

8/9/2019 Rockets BP

6/33


- 6 -

BLACK POWDER ROCKETS

Making Black Powder Rockets

1 increments of clay choke, about a teaspoon. Then black powder #1 to one increment above thespindle. 2 to 3 additional increments of a slower burning fuel, like willow mix or chrysanthemum ofmystery or a color fuel, as long as it doesn't have potassium chlorate for an oxidiser. You want

about a 5 second delay above the rocket for which this fuel above the spindle gives you.

Ricing Black Powder - how much so lvent ?

What I like to do is add enough water with 10 % alcohol added, that when you press it through awindow size screen, you get little worms that fall through that slightly stick to each other. It won't bedifficult to spread this out on paper. If you get big blobs sticking together, then you added to muchwater. I use at least 16 - 18 % weight of water-alcohol mix for all the fuels I make up. With differentmesh sizes of charcoal in the black powder mix that you are making, water percentages will vary toget the exact amount to use. I do know that when ricing a ballmilled mix, such as a willow mix, thescreening process takes more elbow grease to push it through the screen. So if you start withabout 15 % with any mix, this should be OK. In the event you add to much water to the mix, rice itanyway and spread out the globs and let it dry for 20 minutes in the sun and then rice it again, If it's

just right, you will have some fairly fine granules of black powder. This is what I do now with all myblack powder that I make up. I over wet it slightly, screen it and sperad it out on paper and let it dryfor awhile, then re-rice it. What I end up with is the perfect mesh size to make my hybrid # 2 mix.This is exactly the way I do it now for all the black powder mixes I make up. I don't like the coarsemix you get if you only rice it once. It flows nice and settles nice inside the rocket tube when youdump it in. While loading a rocket motor, if you use the clumpyer fuel, it tends to cock the spindleinside the tube when you are pressing up the motor. If you look down inside the motor when youhave it half pressed up, you can sometimes see your spindle isn't in the center of the grain where itshould be. This can bend your spindle if it gets severe. With the finer grained fuel, this doesn'thappen.

BLACK POWDER # 1

75 potassium nitrate

15 charcoal, ballmilled15 charcoal, 36 – 40 mesh

5 charcoal, 80 mesh10 sulfur

5 dextrin, water & alcohol

Delay and tail for rockets

A good delay for such a short distance would be to use willow or tigertail mix. The one I like to useis:

WILLOW MIX

44 potassium nitrate

44 charcoal, ballmilled6 sulfur5 dextrin or 3 parts SGRS

water

You have to wet this and rice it and let it dry before using it. If you press a 3/8 inch column abovethe spindle, this should give yo plenty of delay. If you use enough loading pressure on twoincrements of this above the spindle, you won't need a clay bulkhead either. If your rockets havepretty good zip, then press as much as you can get into the tube. For an even slower delay, youcould use chrisantemum of Mystery which is 50 parts ballmilled charcoal, 45 parts potassiumnitrate, and I always put at least 5 parts of sulfur into the mix, although it's not in the true formula,

8/9/2019 Rockets BP

7/33


- 7 -

and then at least 3 parts SGRS or 6 parts dextrin. This mix also has to be riced and dried beforeuse. These are the main powders I use for my delays in all my black powder motors. To brightenup the tail a bit, you could add an additional 8 parts 400 mesh atomized aluminum to each mix asyou are making it. This gives the tail a brighter hue or kind of increases the light output from thecharcoal.

I only use slow burning fuels above the spindle for my delays, and hardly ever use the same fuelthat the main core was pressed with. Using chrysantumum of mystery is my choice for this

particular type of rocket. It's a very slow burning, very fine spark tail that is very pretty and longlasting, time wise, even if you don't put a heading on the rocket. When you add titanium to this fuel,the charcoal tail is washed out and you get a long hanging, bright white, flowing tail that will form along, 300 foot long tail that forms a large arch in the sky. I found if the charcoal isn't ballmilled veryfine that's used in this mix, for some reason, the titanium won't ignite and burn with this long tail. Infact, the rockets I took to the WWB didn't burn at all, they just went out when the fire hit this area inthe rocket. You could use willow or tiger tail mix to substitute for the chrysantumum of mystery mix,but I prefer to use chrysantumum of mystery mix because it burns so slow. You only need a columof about 3/4 inch in a rocket to get around 5 seconds of burn time. And I use around 1-to 1-1/2''colum in my rockets to get the effect I'm looking for.

Chrysanthemum of mystery Need more sulfur, if you don’t use willow Charcoal

Silver maple makes good charcoal also. It gives a real nice tail and plenty of power also. I've foundthat if used for chyrsanthemum of mystery and titanium tailed rockets where you get the real long,bright tailed rockets, you have to add about 8 parts sulfur to the fuel or the titanium doesn't ignite.Normally, when I used to make those long tailed rockets, I used willow charcoal and only used 3parts sulfur with no problem. But when you use silver maple charcoal, add 8 parts sulfur.

8/9/2019 Rockets BP

8/33


- 8 -

MAKING WHISTLE MIX

Whistle rocket fuels

WHISTLE MIX # 2

76 potassium perchlorate

23 sodium salicylate1 iron(III)-oxid2.5 vasoline (2.5 to 3)

lacquer thinner

WHISTLE MIX # 3

64 potassium perchlorate32 sodium benzoate

1 iron(III)-oxid5 vasoline

lacquer thinner

How to do ?

It takes me about 1/2 hour to weigh out and mix a 1000 grams batch of whistle mix. Once you havethe dry mix ready for the laquer thinner-vasoline mix to be added, it takes another 10 minutes tomix in, then I'm ready to push it through the ricing screen. This takes about 10 minutes. After thericing is finished and the little piles of mix are spread out over the drying paper, it takes anotherhour for it to dry in the sun. The total time from raw chemicals to finished whistle mix is around 1-1/2 hour, 2 at the most. I always start this process around 9 AM so I get the most from the sunsdrying affects. I usually make 2, sometimes 3 batches at a time.I do screen it through a gravy strainer, though, very carefully. The final mixing comes after I addthe thinner and vasoline. I use a 40 mesh screen for all my screening purposes. I don't use it forscreening benzoate or salicylate, though. For that, I use a 12 mesh screen only. After the chemsare screened and you are ready to add the vasoline, I melt the vasoline in an aliminum container,add the lacquer thinner to the bowl of mix and knead the liquid into the mix. This only takes a few

minutes when using a pastry mixer like the wife uses to make pie crusts. I found that adding about20 grams of liquid, lacquer thinner and vasoline mixed to about 100 grams of dry fuel is about theright amount of liquid. If you need more, just add straight lacquer thinner. I find myself adding morethinner as I do this because it drys out real fast. I like the way lacquer thinner evaporates out realfast. If your mix is a little to wet with lacquer thinner, which is the way I always make it, thekneading process is easier. I like it to be a little on the wet side at first so I can smear out thegranuales of benzoate or salicylate in the mix. As I do this, the mix becomes dryer and closer tothe screening texture I want. Mix it real good until you can't see anymore white particles ofbenzoate in the mix after you are finished. When the mix has the right texture, I screen it through a10 mesh screen and spread it out on a large sheet of craft paper to dry in the sun and it’s finished.The best mix to screen has just the right amount of liquid so when you rice it through the screen, itfalls through the screen and spreads out very easy. If you add way too much lacquer thinner at firstand it's like a semi-liquid, just stirr it up in front of a fan with a fork a few minutes. This evaporates

the thinner real quick. and it's right back to a putty consistancy. After you made a few batches, youget the feel for when its ready to rice. When to screen this stuff will take experience. The grainshould feel some what firm but not real hard. You can smash the grains pretty easy between youfingers. If you let it sit in the AR sun for at least 1 hour, stir it around at least once during this time,your mix will be as dried as oven baked. As far as screening the chems together in a dry form, thisoperation is probably the most touchy. It takes a fair amount of pressure to generate enough heatto start burning. The biggest factor in having this material go off unexpectedly as you are making itis generating a static spark. This can happen anytime. Make sure you ground everything in yourwork area, including yourself. I like the texture after screening and drying the mix. It doesn't stick toanything and flows so easy. I would only use lacquer thinner as my solvent. And after it's riced andspread out to dry, it's only a short time later that I can put it away securely and store it out of

8/9/2019 Rockets BP

9/33


- 9 -

danger. All the fuels I make are dried outside in the sun. When dried completely, they go into thererespective container and locked up. I feel very uneasy if I know something is sitting out somewhere drying and not protected from the elements. After you are finished, you have a verypourable, easy to handle grainy mix which doesn't stick to anything. And that's based on my overallexperience for the past 44 years of making rockets.

Vasoline to reduce sensitivity

I would never make it without vasoline. It serves more than one purpose. First, it's a burn rateregulater. Second, it protects the fuel from absorbing water from the air. Third, with this lubricant inthe mix, it presses much easier to a compact grain. And last, which is the most important of all, theaddition of vasoline decrease the sensitivity of the mix when pressing it into the casing. As manyrockets I've made in the past 17 years and never had an accident is proof of this. At least I can sayit does reduce the sensitivity. I do know it's safer to press pyrotechnic fuels if vasoline is present inthe mix.When I first started making whistle rockets, I bound the fuel with NC lacquer. A tiny speck of thisfuel when rapped with a hammer on concrete or steel, it bangs just like a cap. I found that afteradding vasoline to the mix, without using NC lacquer, it's difficult to get it to bang. And the worst ormost sensitive mix I use is the strobe mix. It is a very sensitive mix to both shock and friction. Justtry this experiment on either surface and see for yourself. Once at a PGI convention whilepresenting a seminar on the strobe rocket, I jammed the rammer onto the spindle while pressing

the strobe mix into the rocket. And I had just finished describing how to remove a rammer if youinadverdantly allowed this to happen. What shocked me most was what I had just done, andsecondly, the tremendously high friction that was imposed on the rammer-spindle contact area. Noexplosion. I think God had his Powers working there. Then I had the opportunity to show peoplehow to remove a jammed rammer.

WHISTLE RIPPING SOUND

When I used the higher percentage of vasoline in any of the mixes used for the whistles, benzoateor salicylate, the sound was always more raucous. During the convention at Fargo in 1993 Ibelieve, I used a 3-1/4'' long spindle with a 1'' diameter rocker, and using benzoate with a ratio of64-32-1-5 mix, these rockets had a sound you could not believe. And, of course, I was usingSwedish perchlorate. I simply don't beleive this sound can be reproduced without a good gradeperchlorate.

Catalyst

You could also use copperoxichloride for the catalyst instead of iron oxide which will improve theburn rate of the fuel and make it hotter. You will be surprised how this catalyst improves theperformance of benzoate whistle mix. I've only made a few thousand whistle rockets in the past 15years so I know what I'm talking about.Titanium dioxide use as a catalyst in whistle mix actually slows down the burn rate as compared toiron oxide or copperoxichloride. The only use I found for this catalyst is when I make long windedscreamer rockets and use it mixed in the sodium benzoate fuel as the catalyst. It works quite wellin this capacity.If you want to try making your benzoate mix burn hotter, try using copperoxichloride for the catalist.It will also make the salicylate mix burn hotter also. I asume you are using iron oxide right now. I

found when using this catalist with either mix, you get a hotter or faster burning mix. It seems towork better with the benzoate than with the salicylate or just affect the benzoate mix more.

Difference between salyclate and benzoate whistle

Salyclate whistle used in rocket fuel is the best for power. Benzoate whistle has it's uses in rocketfuel also, but not if you are making a rocket that you want to lift a heavy payload. You could use abenzoate rocket to lift a heavy payload, but the dimensions would have to be larger than thesalyclate rocket.

8/9/2019 Rockets BP

10/33


- 10 -

Salicylate burns faster than benzoate no matter what ratio you mix it or what catalist you use. Forend burn configuration, I've found salicylate to be the loudest. For core burn configuration, themain difference between the two is the raspyness is greater with the benzoate.I can only say that if you make a rocket using the same tooling and use benzoate whistle in oneand salicylate in the other mixed to the same ratio, with no heading, the salicylate rocket will goalmost twice as high as the benzoate rocket.You can increase the altitude of the rocket by increasing the increments of salicylate one at a timeuntil the rocket blows. Then back off one and that is the max amount of salicylate mix you can

press into the rocket before switching to the benzoate mix.

Others

No whistle on take off is a sign of using a poor grade of potassium perchlorate.

Increment size for a 2 lb. LWS should be about 10-12 grams, no bigger.

Testing 4lb. whistle rockets could be a problem because they make so much noise. You can hearthem 3-4 miles away.

8/9/2019 Rockets BP

11/33


- 11 -

HYBRID ROCKET USING THE UNIVERSAL HYBRID SPINDLE

Introduction

Since I first came up with this rocket, I've expanded this spindle to make 4 different motors with itand now call it my new universal spindle. Five different rockets can be made using the universalhybrid spindle.

1. Black powder motor2. Strobe rocket3. Long winded screamer4. Hybrid motor5. Colored tail rocket

So with this one spindle you can make kick-ass rocket motors. The black powder and hybrid motorare the only two that use a nozzle. I use no clay choke above the fuel in my motors except inhybrid motors when lifting heavy payloads because a short delay is built into the rocket whichneeds added strength to withstand blow through. This rocket is a high performance rocket motorwhen made in all the different types. You won't be able to hand ram any of these motors if youdecide to make them so I hope you have a means to press them. The number # 1 hybrid mixdoesn't give a tail to the rocket when fired. So to get a tail, this is where I use the # 2 hybrid fuel.

Hybrid # 1 Mix

The hybrid tooling is designed to use hybrid fuel and a slower burning black powder fuel above thehybrid fuel. First, there is a clay nozzel, then 4 - 7 increments of the hybrid fuel is pressed in, thenthe rocket is finished with black powder to 1 increment above the spindle, then as blukhead anyfuel can be pressed into the motor to give a colored tail or whatever you want it to look like as it'sreturning to earth. The maximum number of hybrid increments used in the rocket before they blowup is 7. You can make this motor any power you want up to power level 7. All of the rockets I havedesigned around that spindle are on the red line already which means if you change any of theincrement numbers, you might have a cato with your rockets. This can all vary with the way youmake your whistle fuel also. Even using iron oxide or copper oxichloride for the catalist makes anoticeable difference in the performance of the rocket. You must use a rocket tool designed to

make these rockets. The loading pressure I use is 8500-9000 psi. The fuel I use in the motors canbe used in all the sizes of the different size motors. So once you make up the fuel, you can makeany size rocket that you may have.

HYBRID # 1 MIX:

The hybrid #1 fuel I use in these rockets is made using:

76 potassium perchlorate23 sodium salicylate

1 iron(III)-oxid2.5 vasoline (2.5 bis 3)

10 charcoal, ballmilled to a very fine powderlacquer thinner

The hybrid fuel is the whistle mix with added charcoal, 10 parts, and it’s ballmilled very fine. Useballmilled charcoal, not just airfloat. After all the ingredients are sieved through a 40 mesh screen,then add the charcoal to the rest of the mix and screen through a gravy strainer. Then melt thevasoline and add lacquer thinner, approximately 20 grams to a 100 grams of fuel. Mix this throughout the fuel until you have a very damp mix and then force it through a window screen and spreadit out to dry.

8/9/2019 Rockets BP

12/33


- 12 -

Black powder # 7 mix:

60 potassium nitrate30 charcoal, ballmilled10 sulfur5 dextrin, water & alcohol

The black powder used is riced with water and alcohol.

Hybrid # 2 Mix

I now have another fuel that can be used in place ot the hybrid fuel. With this method, you docombine the two fuels together and use this as the only fuel in the rocket. With this method, therocket truly looks like a black powder rocket but it isn't and it has kick ass power like the originalhybrid #1.

HYBRID MIX # 2

60 % Whistle mix # 2



lacquer thinner

40 % Black powder mix # 1

75 potassium nitratet15 charcoal, ballmilled15 charcoal, 40 - 36 mesh10 sulfur

2.5 soluble gluttinus rich starch, water & alcohol

100 % total

First you make a batch of straight whistle mix. Then you make a batch of black powder. These twomixes are made up seperately and then blended together. I don't use 5 parts dextrin anymore. Iuse soluable gluttinus rich starch and use only 2.5 parts. Make sure you ballmill one of the 15 partsof charcoal and get it real fine. I usually ballmill mine for 12 hours overnight. The 36-40 meshcharcoal gives the rocket a nice tail. The black powder has to be riced with water an alcohol andthen dried. By ricing the fuel, you mix in the water and alcohol to wet the black powder and thenforce it through 20 mesh screen, spread it out and let it dry. You do the same with the whistle mix,only you are adding lacquer thinner and dissolved vasoline to the whistle mix. Then screen it withthe same mesh size screen, spread it out and let it dry good. The whistle mix is usually pretty softonce it is completely dry, so I put this through the screen also. After these mixes are made up, I always run them through a gravy strainer one more time afterthey are dried to get them pretty fine. What I have been doing with my black powder is to get itpretty wet in the first stage of ricing it. Then I spread it out and dry it for about 25 minutes in the sun

and before it is very dry, I rice it one more time before it gets to hard. This makes a nice grain forblending it into the whistle mix. Then you blend them together at a rate 60 % whistle mix and 40 %black powder by weight. You want a good blend without too many big chunks of either fuel in themixed blend for better results. Press this blended fuel all the way to the top of the spindle with oneextra increment above the spindle, then decide what you want for a tail and press that in. I believethis fuel can be made to be as powerful as the original hybrid fuel. Using the blend method of thetwo fuels together is the only way to get a good tail using whistle mix. I've tried adding charcoal towhistle mix alone and it just wouldn't burn with a tail.To regulate the power of the hybrid rocket change the number of increments of hybrid fuel orchange the intensity of the whistle mix. You get a weaker mix if you use sodium benzoate as the

8/9/2019 Rockets BP

13/33


- 13 -

fuel as compared to sodium salicylate. Salicylate out performs benzoate if mixed to the same ratio.You also can regulate the power of this fuel by adding more or less black powder. Change theblack powder content to 60 % instead of 40 % and get more tail and less thrust. You can play withthis ratio until you get your motors to cato if you are using a good grade of perchlorate to makeyour whistle mix.

Flight Preformance of the Hybrid Rocket

These rockets can lift very heavy payloads. At the convention in Wi. in 2001 I lifted a 6'' diameterballshell with a 1'' motor to a good height. Remember, the ¾” rocket loaded to power level 3 had49.8 lbs. of thrust. With a well made, ¾” version of the hybrid rocket, you can push a 4'' ball shellhigher than what it should go. So to tweek the rocket, use only as many increments of the hybridfuel in the rocket that you need to lift it to a proper height. And anyone who has seen my rockets flywith just a salute heading on them, I always let them come back down a 1000 feet or more sowhen they finally go off, you can still hear them.

Hybrid rocket tooling dimensions

I use a 950 series bronze to make my rocket spindles. First, the spindle is 20% shorter than astandard black powder spindle. The nozzel diameter is larger than the standard black powderspindle. For example, a 3/4'' or one lb. rocket motor, the diameter. of the base of the spindle is

0.430” and the length is 4.2 '' long. Scale this up or down to get other size spindles. The base hasthe 30 degree taper which is typical of a black powder spindle and this dimension is included in4.30 inch length. The taper on the spindle is 1-1/2 degrees. The tool set also needs 3 rammerswith holes and 1 solid rammer. The black powder motor you build with this spindle will be as goodas any black powder rocket you can make.

8/9/2019 Rockets BP

14/33


- 14 -

3/4” WHISTLE ASSISTED COLORED TAILED ROCKET


WHISTLE MIX # 2



lacquer thinner

Making whistle assisted colo red tailed rocket

There is no nozzle used in this rocket. For the colored tail rocket, press in three increments of #2whistle mix, then press the color of your choice to about 1 inch above the spindle. Most coloredfuels burn not too fast so 1 inch above the spindle is a starting point. Vary the amount above thespindle to get the required delay. If the colored fuel burns real slow, just add and extra increment ofwhistle to the rocket before starting the colored fuel.

If using the hybrid spindle to make these rockets, without a nozzle, press in three increments of thefastest whistle mix you can make, using sodium salycilate. This will take up about one inch of thespindle length. (¾”size rocket: 3 increments = 1 inch). Use only 7 grams for each increment in a ¾”size rocket. Total 21 grams of whistle mix, then finish with black powder or use a colored fuel for acolored tailed rocket, like the magnesium red, Steinberg formula to about ¾” above the spindle.Loading pressure on these rockets is around 8500 psi. These will be kick ass rockets because ofthe long spindle, but you don't need to use this long of a spindle to make red tailed rockets. Thesethings take off so fast, you don't even know that the first few increments pressed into them iswhistle mix. This is what gives the rocket it's boost on takeoff. And the red color is there at thesame time. You can even make a red tailed rocket using a shorter spindle such as the standardwhistle rocket spindle which is about 2-1/4 inch long by using the same technique, whistle and thenthe red formula.

This is the formula I use for my red tailed rockets only I use -200 mesh magnesium and 5 partspotassium dichromate. I then bind with NC and acetone. The parlon makes it pretty sticky whenricing but this works good when used in all my rockets where you see a red tail. This formula wasthe original chuffer formula that you gave in your post that Doc Steinberg used at my house back in2001. He didn't use any potassium dichromate or acetone and NC lacquer. Shelf life on this ispretty good also. The last batch I made is over 2 years old and still works good.

The hybrid tooing you have is perfect for what you want. Just take either the red or greenmagnesium composition you have already, and start with 3 or 4 increments of the salyclate whistlecomp on the instruction sheet, then finish your rocket with either color comp. What you will have isa very fast flying green or red rocket. Try it before you consider another spindle and see what youdecide. So the loading steps would be: press in 3 increments of whistle first, then press in theremaining space in the rocket with the color comp. Once you have about 5/8 inch above the color

that you chose first, then you could use the other color above that so the change goes from red togreen or green to red. Or, make the increments 1/4 inch thick above the spindle and press in red,green and back to red or just the opposite so you have a three color change.

8/9/2019 Rockets BP

15/33


- 15 -

LONG WINDED SCREAMER ROCKET


WHISTLE MIX # 2



lacquer thinner

WHISTLE MIX # 3

64 potassium perchlorate32 sodium benzoate

1 iron(III)-oxid5 vasoline

lacquer thinner

Making Long Winded Screamer Rockets (LWS)

There is no nozzle used in this rocket. 4 increments of whistle mix #2. Then whistle mix #3 all theway to the top of the rocket tube. Leave enough space to grab the motor with a vice grip to pull itoff the spindle after inserting the solid rammer into it. On the increments above the spindle, Ialways add flake titanium in each scoop before I press it in.

Pressing Long Winded Screamer Rockets (LWS)

I have used loading pressures on LWS anywhere from 7000 to 9500 psi. If it works at 7500 psi,don't use any more pressure. I've always used New England tubes so I know what kind ofpressures these tubes can take. Just remember when you start pressing the first few increments,don't go up to the calculated pressure right away. Start at least 1000 psi less than what you finishthe rocket with. And as you press up the spindle, increase the pressure gradually until you reach

the calculated number. As you can see, on the first press, you are only pressing on the fuel aroundthe spindle so you aren't pressing on the full diameter of the tube. If you start right at 4'500 poundsof force, the actual loading pressure will be around 11'130 psi. Don't worry about maxing out yourPressure Force Gauge. It can take it.

I also found that using benzoate whistle that is used above the salycilate whistle mix in the LWSrocket, if it is catalized using copper oxichloride, this will also cause a cato. So if making a LWSrocket, use only iron oxide in the mix. Using copper oxichloride makes it burn to hot. When ever Imake these rockets, I always use at least 9000 psi loading pressure, and sometimes I accidentlybump it up to a lot more. And I've found that more is better than not enough. What I also do with afinished rocket is to place the plastic bag into a ice cream bucket with a good fitting lid for extraprotectio

Better screamingUsing a good grade potassium perchlorate for whistle mix is the answer to very loud, screamingrockets. I have used just about every kind of perchlorate there is available and found that the twobest potassium perchlorates to use are #1, Swedish potassium perchlorate and #2, Taiwanese.These two potassium perchlorates give the best sound. Also, use copperoxichloride for the catalystinstead of red iron oxide. I know Swedish is not available anymore and have starting using. Thelonger the core into the fuel that is made, the louder the scream also. There is no need to recessthe fuel into the nozzel end. When using a good grade fuel, it will scream damn good without therecess. I suspect the perchlorate you are using is a cheap, chinese grade and you never will get

8/9/2019 Rockets BP

16/33


- 16 -

that stuff to whistle very loud. Make sure you know what type of perchlorate you are buyingbecause it has a most profound effect on the whistling character of the mix.

Flight time

There is only one straight whistle rocket, the Long winded Screemer on that sheet of instructions,and if you don't do it exactly the way it says on the sheet, good luck. Just make sure you use along fuse on the rocket. There isn't to much latitude on making up that rocket, but when made with

properly made fuel, you will be amaized how well it flys. 15-18 second flights will be average beforethe heading activates and the rocket will still be up a long way.

8/9/2019 Rockets BP

17/33


- 17 -

ENDBURNING ROCKET

Making endburning rockets using hybrid mix # 2

I now use the # 2 hybrid fuel exclusively in my endburn motors. Making Estes motors has been alifetime passion of mine. I make a special spindle that looks similar to Estes nozzles. It is oilhardened to stand up to the pressures that it takes to press these motors. Also, the first rammer is

made from aluminum with an insert of the same material that the spindle is made from. Theendburn spindles are not stainless steel. They are made from 4041 alloy steel and will rust in youlet them, so keep them oiled when not in use. I use 4140, alloy steel and oil harden each onebefore I use it. You can't touch it with a file. I don't know what the hardness is, but I do know that itis some where above 60 rockwell. And I only use New England paper tubes to make these motors because they are the only kind thatwill work consistantly. The fuel that can be used is straight black powder made to burn as fast aspossible. The other fuel that can be used is what I call # 2 hybrid fuel, which is a blend of whistleand black powder. You need costly equipment to make them, meaning a good hydraulic press withcapabilities of measuring loading pressure.Once the rocket has burned off 3/4 of it's fuel, then the speed gets pretty high if you don't have avery heavy heading on it.

HYBRID MIX # 2




lacquer thinner




100 % total

To increase the power of end burn ing rockets, add whistle mix (Hybrid #2)

The best way to increase the power of your black powder would be to add whistle mix to it insteadof making black powder using potassium perchlorate alone as the oxidiser. For maximum power inan endburn motor with a good tail to boot, I use, what I call my Hybrid #2 fuel. What's nice aboutusing the Hybrid #2 fuel in endburners or the hybrid rocket, you can change the ratio of BP towhistle mix and play with it to get any power you want. It doesn't matter what kind of perchlorateyou use with this, because you can vary the strength by varing the two ratios. Change the black

powder content to 60 % instead of 40 % and get more tail and less thrust. With this mix, I've won afew trophys at the PGI in my endburn rockets. The fuel burns very fast and the extra coursecharcoal gives off a nice tail. And the most important thing to do when making these rocket enginesis to use a sleeve on the tube and press them to at least 8000 psi or they will just blow apart. I usearound 9000-9500 psi. And the next most important thing is to use only New England, virgin krafttubes. You cannot make an endburn rocket longer than 2-1/2 to 3 inches if using cheap tubesbefore you get a burn through in the sidewalls of the tube. If you don't have New England tubes,then the whole task becomes real difficult and I wouldn't even try to make them. I found that theburn rate for this fuel is about 1 inch per second or slightly less.

8/9/2019 Rockets BP

18/33


- 18 -

The endburn rocket I won competition

The endburn rocket I won competition with was a 3/16 wall, I inch ID rocket made with NewEngland Papter Tubes (NEPT). It was pressed to 9000 psi. The fuel consisted of 50 % whistle mixmixed to a ratio of 76-23-1-2.5 which is potassium perchlorate, sodium salicylate,copperoxichloride and vasoline respectively. The other 50 % of the fuel was 75-15-15-10-2.5 blackpowder that was wetted and riced and dried. The ratio was potassium nitrate, ballmilled charcoal,36-40 mesh chaocoal, sulfur, and soluable glutenous rice starch respectively. The ratio of fuel wasmeasured by volumn, not weight. You can regulate the power of this fuel by varying the blackpowder percentage in the mix. Only by making the two fuels seperately and then mixing togetherafter dried can you get the charcoal tail that this fuel gives to the rocket. You can regulate thepower output of the fuel and it give a nice tail. You could always increase the amount of salicylatein the mix also to slow it down but I never did it this way. It won't be difficult to control the burn ratebecause all you have to do is add more black powder to the mix, say a 60-40 ratio with the 60being black powder. I like the power of whistle mix for endburners. They out perform black powderfor the obvious reason and don't require the high loading pressures the black powder does.

Endburning rocket made from commercial black powder

I have made endburn motors using straight black powder, using commercial made 3fg and 4fg butthe loading pressures to remove all the little grains into a solid mass goes up to about 15,000 psi. Ihad to use a solid sleeve made from steel in order to do this. I have pressed some of the New

England tubes to a loading pressure of 30,000 psi without destroying the tube. Until I polished theinside of the sleeve to a bright, mirror finish, I couldn't even push the tube out of the sleeve after itwas finished. By the way, the 30,000 psi loading pressures I did was on a .100 thick walled tube.When there isn't much wall to crush, you don't have these problems with smashing down the tube.Just use small increments as you press.

If I would have used meal powder instead of 3fg, You might be able to reduce the loading pressureby a few thousand psi. If you use black powder only to make your rockets, you will have to wet itand rice it, ''push it through a Screen'' and dry it. If you don't do this, the powder will burn muchslower than ''riced powder''. After ricing the powder, you have a nice flowable, dustless fuel that ismuch easier to work with also. Ballmilling the fuel over night would improve the burn rate and get itto burn as fast as possible. I also used willow charcoal but any charcoal will work. I was neversatisfied using straight BP to make my endburn rockets though. You get so much more powerwhen you add whistle mix to the BP.

Another way to use your whistle mix in an endburn configuration would be to add ballmilledcharcoal to you straight whistle mix. Start out by adding 5 parts to a 100 gram batch of whistle mix. Add the charcoal right along with the other chemicals before you add the vasoline or whatever youusing. This is what I call my hybrid #1 mix which I use in a core burn rocket. The added charcoalslows down the fuel just enough to prevent catoing. If the motor catoes, add 10 parts charcoal toeach 100 gram batch. Just keep adding charcoal until the rocket stops catoing. Remember to addballmilled charcoal, the finer the better.

New England Paper Tubes

I disected a New England Paper Tube (NEPT) and found there are 4 layers of paper glued

together. Then, these four layers are rolled together to form the tube. I would love to see just howthis operation is performed. This must be a trade secret because no other company in the USAmakes these kind of tubes. The best wall thickness to use is 1/8 inch walls. I can press a rocket 7inches long without burn through. And use a good fitting sleeve on all your tubes.

Nozzle diameters for endburn rockets

To give you a heads up on nozzle diameters for endburn rockets, I use for a 1/2'' rocket a diameterof .120 thousands. For a 5/8 dia. 0.140, a 3/4'' rocket 0.165, a 7/8'' dia. rocket 0.180 and the 1'' idrocket at 0.220. I just made my first 4 LB. endburn and made it to 0.340 and tested the fuel I use inall the other ones and it seemed to work pretty good. Have the first rammer tapered on the end to

8/9/2019 Rockets BP

19/33


- 19 -

about 80 degress included angle or 40 degrees on a side and the exit part of you nozzel tapered to30 degrees included angle or 15 degrees on a side. This angle is what Estes uses on the motorsthey make. If it's good enough for them, it's good enough for me also.

Nozzle Erosion

What you could do to allow for the nozzle erosion as it burns farther up the grain, press a hotterfuel into the motor. I've done this before on the longer motors that I've built. Since the nozzle is

slightly enlarged, it could use a faster fuel burn without a cato. Just a thought.

8/9/2019 Rockets BP

20/33


- 20 -

STINGER MISSILE

Making st inger missile using hybrid mix # 2

What I use for fuel in these short spindled rockets is my hybrid #2 fuel. This fuel gives a nice tailand very powerful and less likely to cato then straight whistle mix. Press a clay nozzle. Then usethe # 2 hybrid fuel all the way to the top of the spindle and then finish the rocket with anything you

want for a bulkhead. With the stinger tool set, you will be able to make a pretty powerful coreburning rocket also.

HYBRID MIX # 2




lacquer thinner




100 % total

The main factor when using a stinger spindle is to make sure the side vent drilled into the sidegoes through clay before it hits fuel. A special rammer make for the first increment of clay rammedinto the rocket should be made first with a longer than normal taper to accomplish this. With theexhaust from the small hole going through clay first, erosion will be minimal.

Several factors determine how well your rocket will perform. First, an increment of fuel pressed intothe tube shouldn't be more than 2/3rds. the diameter of the tube. Second, the loading pressureshould be around 6500 psi. If they still blow after doing this, add an extra hole to bottom of therocket, exactly opposite the the first one. If they still blow, add another hole to the bottom of therocket and space them 120 degrees apart. I use two side vents in each motor and they really buzzon take off. Very impressive little rockets. Start with 3/16 holes on each side and make themsmaller until you get a cato. Maybe you won't have to downsize the holes at all. These will be thebest sounding hummers you ever heard.

Making st inger missile using whistle mix #2

Also, this spindle would make a very powerful whistle rocket by using straight whistle all the wayup. There is no nozzle used in this rocket. It should work with a mix of 76-23-1-3 salycilate or

benzoate mix. If it blows, then use a 70-3-1-3 mix instead. They have to be pressed using 9000 psiloading pressure. If using #2 hybrid, don't forget the nozzle.

WHISTLE MIX # 2


1 iron(III)-oxid2.5 vasoline (2.5 to 3)

lacquer thinner

8/9/2019 Rockets BP

21/33


- 21 -

STROBE ROCKET

Making st robe rockets

There is no nozzle used in this rocket. Start with 4 increments of whistle mix #2 and then strobemix #4 to 1/8" above the spindle, then finish with 2 - 3 more increments of whistle mix #2 for a bulkhead.

WHISTLE MIX # 2


1 iron(III)-oxid2.5 vasoline (2.5 to 3)

lacquer thinner

STROBE MIX # 4

60 ammonium perchlorate25 magnalium, 50-50, -200 mesh15 barium sulfate

5 potassium dichromate

NC lacquer & acetone, about 10% mix of NC lacquer

Just make sure the increments for each press is not more than 3/4'' high after you press it into thetube. The only thing that will cause either of these rockets to cato is too much salycilate whistle mixpressed in first.

Preparing strobe mix

What I suggest you do is once you have all the chems to make your strobe mix, start with thesmallest batch you can make up and test it first for strobe rate while it's burning. You can make astrobe rocket with any strobe rate that it burns with, but to make a good, keep climbing type ofrocket, the strobe rate should be pretty fast. You have to start some where so this is what Isuggest, and what I use for my strobe fuel: 60 AP, 25 magnalium, 200 mesh, 15 barium sulfate, 5

potassium dichromate. Wet with NC lacquer dilluted to 10% with acetone. It doesn't matter what %you use, really. Mix it in good and get the mix pretty wet. Then rice it through a gravy strainer orwhatever you have available. While it is still wet, pinch a tiny pyramid of comp and set it aside todry for 15 minutes. What you want is a small pellet that is firm and solid to test. With a lightedmatch, test how it takes fire and watch it burn and note the strobe pulse. To increase the strobepulse, you can do this two different ways. Reduce the mesh size of the magnalium or introducestraight magnesium powder into the mix, keeping the metal content as 25 parts. I have found thatsubstituting 1-1/2 parts of magnesium into the mix increases the strobe rate. It will vary accordingto the mesh size of the magnesium. I suggest using the finest magnesium you have. The 2 micronatomized magnesium works good. I mostly used 400 mesh granular magnesium. If you go theother way and change the mesh size of your magnalium alone, it will take some expermenting.Just change the ratios of the mesh sizes you mix together. If you still have a slow strobe burn rate,then I suggest you use and combine both methods together. By making small batches and testing

first, you won't have a whole bunch of almost usless strobe mix laying around. As for thesuggestion to substitute the barium sulfate with strontium sulfate, this is what I use to make my redstrobe mix with. The formula I use here is a slightly modified Simizu formula: 48 AP----22 atomizedmagnesium-100-150 mesh----6 parts granular magnesium-400 mesh---19 strontium sulfate----5 P.dichromate. Bind with NC lacquer and rice. I should mention that I use 90 micron AP in both mixes. Any more questions and I'd be happy to ramble on.

NC Solution

I've used 25 % premade NCL and used up over a pound of smokeless powder to make my ownNCL. It doesn't matter what the concentration of NCL you use to make strobe mix for rockets. All I

8/9/2019 Rockets BP

22/33


- 22 -

do is mix about 2 tablespoons of smokeless powder in a quart jar with acetone filled to 1/2 inch ofthe top and let it dissolve for about 3 or 4 days. Shake it up every day until it's dissolved and thenuse about 2 tablespoons of this mix added to a 6 ounce cup and dilute it within a 1/2 inch of the topwith acetone. Stir it up and it's ready to use. This is about enough to moisten a kilo of strobe mix. Iget it wet enough before I rice it and spread it out and dry. While I am mixing it in, if it doesn't getwet enough, I add only acetone to the strobe mix. I've done it enough times and never measured it,but I usually get it pretty wet with the acetone wetted NCL. It's like a syrup before I add the acetoneto the mix. I think I used about 3 tablespoons of smokeless powder once when I was making up a

batch in a quart jar and it was so thick, I poured half into another jar and added acetone to each jarto fill it up. It still was heavy enough before dillution. The smokeless powder I used was a singlebase powder also. Made sure that's what you use to make your NC lacquer.

Strobe rocket mix - strobe rate

If it still strobes to the ground then your strobe is burning way to slow and probably your whistle mixis way to weak also. If you can't make your strobe mix strobe fast enough then your barium sulfateis the culprate. This chemical is probably the most biggest reason people have problems withthey're strobe rockets. Get a different batch of barium sulfate or add the finest granular magnesiumyou can find at about 2-3 parts per 100 gram batch and leave out the same number of grams ofmagnalium. You have to have the right strobe rate to the mix or the rocket just doesn't fly highenough. Also, if the whistle mix is fast enough, you lose height also.

Increase the strobe pulses per second

I also found that barium sulfate, when used in the strobe formula that I use for strobe rockets, canbe blamed for a slow strobing pulse rate if it is not pure. I have no way of testing barium sulfate forpurity because I am not a chemist but have narrowed it down to this chemical as causing all theproblems I have encountered with strobe mix. The strobe rate should be just right to make a goodstrobe rocket but there are ways that I have found to tweek the mix if your barium sulfate is taintedwith impurities. I've always wondered where I could get pure barium sulfate to test my suspicion ofthis chemical being the culprit of crappy strobe mix. And what I mean by crappy is that the stroberate is very slow when burned. The best way to increase the strobe pulses per second is tosubstitute a few parts of very fine, granular magnesium in place of the magnalium in the mix.Whenever someone asks me how to make strobe mix, I always tell them to make a tiny batch first

to test and see if you have good barium sulfate. Almost always, the mix has to be tweeked to getthe right strobe rate before it can be used in a strobe rocket.

Strobe rocket mix - sensitivity of formula

I don't think there is a more sensitive mix than strobe mix. When you test this stuff on a steel anvilor on concrete both in friction and pounding on it, it scares me every time I do the test to showsomeone how sensitive it is. Yet, I've never had an accident when making strobe rockets. Strobemix can explode, when two metals come in contact with each other with a small amount of fuelbetween the metal. It won't happen every time because I've proved that. But I heard of one guythat let his buddy press up a few strobe rockets and one of them blew in the process. What he didwas use the solid rammer to soon and pressed down onto the tip of the spindle. The guy got hurtbut not to serious. So remember that when you are pressing up rockets, don't let your

concentration wander. That's the biggest problem I find when pressing rockets for a few hours at atime. And don't be in a hurry when pressing them either. Your thoughts cannot wonder during thistime.

Pressing strobe mix - Danger

Adding titanium to a whistle mix just makes it more sensitive when pressing. I know of one incidentwhere, while pressing a small comet using strobe mix, the operater let the comet sit underpressure for a few moments. He turned away and took a few steps and it went off. Since then, Inever let the pressure sit on any kind of mix I'm pressing. I've always told anybody that presseswhistle mix, don't let the pressure well on the mix. Release it immediately. Although I never press

8/9/2019 Rockets BP

23/33


- 23 -

whistle rockets with titanium in the core, I do use it in the delay portion of the rocket. In the tens ofthousands of whistle rockets that have been pressed in the past without incident, it proves it canhappen. I still think the titanium played a big part in your mishap, but we will never really know forsure.

Store strobe rockets

Why did they blow up. That's a good question. Probably the most important factor in making these

rockets work in the first place is loading pressure. Second, was the fuel completely dry when theywere pressed up ? Third, were they kept dry since they were pressed ? Storing these kind ofrockets, ones with whistle mix and strobe fuel for more than a few months, in an environmentwhere the temps are up and down affects the performance of these rockets. If the rockets werestored in a air tight containers, and the fuel wasn't completely dry when pressed, good luck. Thereare a whole bunch of things to consider if you plan on storing these kind of rockets motors for anylength of time. Even if the tubes you were using had be exposed to a lot of humidity before theywere pressed can affect a stored rocket motor. It all boils down to moisture. Whistle fuels andstrobe mix don't like moisture. If you can keep this out of the picture, then a lot of problems wouldbe solved.What I suggest you do is press up a few using at least 8500 psi loading pressure and then placethem in a double plastic bag with a dessicant bag also, and let them sit for a few months. Justmake sure the fuel is absolutely dry. Then test fire one right after you press it to make sure you

haven't screwed something else up.

8/9/2019 Rockets BP

24/33


- 24 -

PRESSING ROCKETS

Hose clamps on sleeve

Over the past 16 years, I gotten used to using PVC split sleeves. It takes me around 2 hours tomake a sleeve from PVC to fit the 1-1/4'' new england tube sold by Jim B. You have to start with 2''PVC and get it down to fit a 1-3/4'' tube. I prefer PVC sleeves, because they're just easier to make

and still work good, in my opinion.First, get your sleeve to fit without being completely closed around the tube when the clamps areon and tight. If you didn't have a gap in the sleeve, the tube would be loose in the sleeve, or slightlynot tight. Second, just make sure you support the sleeve with as many hose clamps as you can puton it. A lot of people leave to much room between hose clamps, when they press rockets and thisleads to problems. Place them as close together as you can get them and right up to the top of therocket casing. When I'm using a long sleeve to make a rocket, I use a powered screw driver toremove the clamps. The PVC sleeves work on all sizes and is easiest to make.One thing that's important when removing the spindle from the motor, do this only after it'sremoved from the sleeve. This allows the motor to relax slightly, and the spindle will come outeasier. Otherwise the sleeve has a tighter grip on the internal portion of the motor and after thesleeve is removed, the spindle will be slightly relieved.

BP loading pressure

A rule of thumb that I use for loading pressure is 6500 psi. If you use this pressure on all yourrockets, the burn rate of the black powder can be pretty fast. Whatever the ratio you are using rightnow and your rockets are working good, increase the Nitrate content by 5% increments and stopwhen your rockets begin to blow up. Then use the last mix you made where they worked. You willbe suprized by the increase in performance of you rockets by pressing them instead of poundingthem. By the way, my loading pressure that I use on any rocket I make is around 8500 psi.

You need less pressure force for the firs t increments

The first increment is pressed to a lot more loading pressure that what is calculated for the entirediameter of the rocket tube. And with the increment being on the extreme end of the rocket, itburns up pretty fast and never has really given me any problems.Just remember when you start pressing the first few increments, don't go up to the calculatedpressure right away. Start at least 1000 psi less than what you finish the rocket with. And as youpress up the spindle, increase the pressure gradually until you reach the calculated number. Asyou can see, on the first press, you are only pressing on the fuel around the spindle so you aren'tpressing on the full diameter of the tube. If you start right at 4'500 pounds of force, the actualloading pressure will be around 11'130 psi.Calculate the area of your spindle at the bottom and the top. Notice the difference and thencalculate what force change you would have to make to keep the loading pressure the same all theway to the top of the spindle. If your spindle doesn't have much taper to begin with, just keep theforce the same all the way and don't worry about it. I use around 9000-10,000 psi on all my rocketsI press.

Pressure Force Gauge ConverterIt's easy to confuse the two terms of pressure and force. Force is the actual weight that is put uponthe rammer, like putting a car on top of the rammer. Pressure is the amount of weight on a givenarea. All gauges are calibrated in psi. And yes, the pressure force (PF) gauge has a piston insidethat is 1 square inch in area. So when a force is applied to it, it reads out in psi and since it'sapplied to one square inch of area, it also reads out the actual force applied also. In order tocalculate loading pressure, you have to know the weight applied to the rammer. The pressure forcegauge tells you that right away. Divide the reading by the tube area to get loading pressure.Example: The area of a ¾ inch tube is 0.442 square inches. Divide 2'873 pounds by 0.442 andyou get 6'500 psi. Divide 3'757 pounds by 0.442 and you get 8'500 psi. Harold Bentley was the firstto use this idea a few years ago.

8/9/2019 Rockets BP

25/33


- 25 -

The tube wall s tretches and the paper tears apart from high loading pressure.

I use only New England high quality tubes to make all my rockets motors. If you use a thick walltube made with a cheaper grade paper, then you really can't use a high loading pressure such as Ido. When using a high loading pressure with thick walled tubes, the tube wall can becomecompressed outward and downward and what happenes then is the tube wall stretches and thepaper actually tears apart and the wall becomes very weak. This can happen with the moreexpensive New England tubes also. Thats why I say 6500 psi should work good. Any pressurehigher on a thick walled tube could start to tear the paper fiber and weaken the tube.On all my endburner rocket motors, I use a thin walled New England tube with only a 1/8 inch wall.These motors are pressed to 9000 psi and still maintain there wall integrity because there isn't somuch paper to compress. Of course, the internal pressure isn't present during firing as you wouldhave in a core burner.The wall thickness on my tubes that I use to make hybrid motors are 3/16 inch but I still press themto 8500 psi. Press up a motor using 8500 on a thick walled tube and then cut it apart and tell mewhat you found. There will be tear lines going up the tube that will be at least one half or threequarters deep in the wall of the tube. And you wonder why the rocket blows when you fire it. Thereisn't any tube wall left to support the internal pressue generated. So I suggest using a good gradetube to start with.

Increments

An increment, after it's pressed into the rocket, shouldn't take up more than 2/3rds the diameter ofthe tube itself. As long as the increment doesn't take up more than 2/3 the diameter of the tubeyour are pressing, this is just about right. My increments are probably closer than 1/2 the diameterof the tube. Small increments are better that larger ones.

With a ¾” tool set, 7 grams is about maximum for an increment. This is about one scoop, or oneslightly rounded teaspoon. And in a 1/2" endburner is about a level 1/2 teaspoon. That's probablyaround 4 grams.

The old tale of an increment should be equal to the diameter of the tube just won't work on themore powerful, high energy fuels being used today, including black powder. I don't think rocketswere pressed, using a hydraulic press when that statement was rule of thumb. A modern day blackpowder rocket out performs the old black powder rockets that were made by pounding years ago.Buy the way, the black powder rockets I press today are pressed to 8500 psi without any problems.

To large Increments

To large of an increment will cause those rings around the tube. Also that's why the ram is sticking.For some reason, when using the same amount of fuel for an increment, volume wise, blackpowder will do this. You can hear the creaking or snaping sound as you press on the increment inthe higher pressure stage. This is your tube crushing downward and causing those lines in thetube. Just use less of an increment for each press. You may still get some lines in the tube, butdon't worry to much about it. I would have also said your sleeve doesn't fit tight either. Use asmany clamps on the sleeve as you can get and as close as possible to each other. The reason youdidn't get those lines on your old tubes is because the cohesion of the paper in those cheapertubes gives more easily on the inside of the tube and doesn't extend to the outside, where you can

see it. I get those lines on most all of the rockets I make, but some are more visable than others.

Spacers to reduce travel of the hydraulic press

When ever I made a larger rocket using longer tooling, I place spacers under the tooling. I only use1 inch of travel in my hydraulic press. I just insert or remove spacers under the tooling I'm using.The farther you extend the ram on any kind of hydraulic device, the more wobbly it becomes andintroduces an unstable condition. Figure out a way to place spacers under you tooling to raise andlower the height of your pressing needs. I have a bunch on 1/2 inch thick plastic pucks, somethicker, that I machined flat and use those under my tooling. I also have some pieces of steel pipeabout 3 and 8 inches long, with a plate on top to set the pucks onto for large distance changes.

8/9/2019 Rockets BP

26/33


- 26 -

When pressing small endburners, I use the 8 inch pipe spacer and a plate on top with a bunch of1/2 inch spacers on top of that and remove the 1/2'' spacers as I press up the motor. All thesespacers have to be perfectly square, including the pipe. I machined them in a lathe to make sure. And last, if your press isn't perfectly square with what you are pressing, with all the spacers inplace, it's junk. So just make sure everthing is square and very rigid. If you get any sidewaysflexing, fix so it doesn't do this.

Misalignment in the press Any misalignment in the press will bending your spindle. But why: When pressing with a longspindle, you will note as your pressing progresses up the spindle, that your spindle is no longer inthe center of the tube when you look down into the tube. That's caused by not pressing evenly. And if the comp isn't perfectly level before you press the increment, this will only amplify theproblem as you press up the spindle. Woody had this problem at the convention this year and Ishowed him how to correct this problem. Take a skinny dowel or a welding rod long enough toreach to the bottom of the increment just dropped into the tube and swirl it around until you level itoff before pressing. Do this with each increment until you can visually see each increment that youput in, and note each increment to see if it is level before pressing.

On the bent spindle, make sure the hole in the rammer is clean also. If composition was filling upthe hole, then you are pressing against a dead head inside the rammer. It is absolutly imperative

not to allow fuel to become built up on the inside of your rammers. This is a problem that can leadto bad consequences. Always look into the rammers before each use and check to see if any fuelis built up inside. This reduces the size of the hole and it will jam on the spindle before it reachesthe line scribed on the rammer. At least I hope there is some kind of marker on the rammer toshow where this will happen. At least, put a piece of tape on the rammer to show the jam line. Afteryou are finished with each rammer, clean it out before setting it down and going to the nextrammer. I use a jackknife to scrape out any build up of comp inside my rammers with a very gentlemotion, trying not to scrape any metal out. My rammers last forever. After 10 rockets, I put myrammers in my lathe and polish out the bores with Mother's Mag-Aluminum polish to a bright, shinyfinish. This keeps the comp from sticking tight to the rammer for awhile. What you could do is get asmall dowel or drill bit and wrap tissue around it and put a dab of polishing cream on it and run itinside the bore to clean it up. Use a hand drill to spin the dowel.

Remove an jammed rammer

I once had to remove a jammed rammer from one of my new customers spindle. What I do is cutoff the tube and remove all the fuel from around the spindle. Then I place the base in a vice and tryremoving the rammer by any means first. If it won't move, I then heat around the rammer with apropane torch to expand the aluminum. After a few seconds of heating, bang! The rammer flew offthe spindle and hit me in the hand. That tells me there was comp inside the rammer. I learned mylesson also. I don't know if the rammer was close to the jam line on the rammer or not but therewas fuel composition inside the rammer. Don't let this happen to your rammers.Make sure everthing is removed from the tooling and you just have the bare tooling with the stuckrammer sitting on the spindle. Place the base of the tooling in a vise and tighten is up so it can'tmove horizontaly. Take a vise grip pliers and snap it onto the rammer near the end of the rammer.Then take a propane torch and heat up around the entire circumference of the rammer with out

getting any heat on the spindle for about 6 or seven seconds. Don't stand in front of the rammer,the direction it is going to come off the spindle. You might have a little comp inside the rammer thatwill ignite when you heat it and it will come off the spindle very quick. After heating it, twist and pullon the vice grip to loosen the grip of the rammer. If it doesn't move at first, heat it some more andgive it another try. It should come off after heating it up and expanding the rammer slightly. If itdoesn't come off, cool the entire set up in a cold pail of water and try again. You may have to getaggressive on the vice grip this time. This method has worked for me ever time.

8/9/2019 Rockets BP

27/33


- 27 -

ROCKET ENGINE CASINGS

Motor casings soaked in wood hardner

I've soaked some of my 3/4 inch NPT motor casings in wood hardner. It really seems to increasethe wall strength of the tube. What I was interested in doing was to make the ends of the tube itselfstronger. That way, an epoxy used to glue in the bulk head would hold better. With a paper tube,

the only holding strength you have is only as deep as the next layer of paper and glue. By usingthe wood hardener, and soaking the tube for an hour, the hardener would soak deep into the paperand make it one solid thickness. This is what you need to make a composite motor, one solidchunk of tubing. This would also hold the nozzel intact.

Tube loading pressure test

Don't let wall thickness of a tube gives you a lot of strength to the tube. It does if you are handramming a tube but when you begin to press rockets, wall thickness doesn't mean poop. Why doyou think Estes model rockets are made from such thin tubes ? The wall thickness on the Dengines is only 0.100 thick. These motors are pressed to at least 15'000 psi or maybe more. Whathappenes to the wall of the tube when subject to that kind of pressure ? It compresses down andoutward or gets thinner. What happenes to a thick walled tube if you squeeze it down with 15'000

psi. It does the same thing but more so because the wall is so thick because of all the paper. Whathappenes then ? The wall actually stretches so much outward and downward, the paper tears itselfand leaves you with a breeched tube. You can't see it from the outside but if you cut open the tube,you will find tears along the walls going up the tube. Now the wall is only 1/16 inch thick that isn'tbroken. What's left is a 1/4 inch walled tube with probably a wall thickness of 3/16 left and it's splitmore than half way through. If you don't believe me, I have proof of this. Even a good NEPT will dothis if too much loading pressure is used. These two operations of making rockets by pressing orpounding will vary the result, depending on the condition or type of tube you are using. You canonly make an endburner from NEPT tubes more than 5'' long before it burns through the side wallof the tube. I know some guys make them longer for drivers on wheels and girandolas, but theywouldn't fly by themselves and go 4000 ft. high. I'm talking about high power rockets that use a fastburning fuel and that need at least 8000 psi loading pressure. And the whole idea here is pressingthe motors using thick walled tubes and using high loading pressures. It just can't be done using a

cheaper, thick walled tube.

A good, s trong, hard wound tube with a thin wall is better than a thick walled, sof ter woundtube

A good, strong, hard wound tube with a thin wall is better than a thick walled, softer wound tube formaking rockets or any other kind of device that requires pounding or pressing of the compositioninto it. The simple reason for this is because of the wall thickness of a tube will determine howmuch it will distort during the pounding or compressing that you give it. It also depends on the typeof paper the tube is made from. I've seen some pretty good tubes made from a good grade kraftpaper and some tubes made from a thick paper board with thick walls that weren't worth formaking rockets. And since I believe in using extreme forces to press rockets, the wall thickness isvery important in determining the strength of the finished product. What really determines the

quality of a rocket is what type of tube you make if from. That's why I use New England papertubes made with virgin kraft with walls no thicker than 3/16 inches. The end burn rockets I makehave a 1/8'' thick wall and the heavyer tubes have a 3/16'' wall. If the wall thickness is greater than3/16'', the paper will compress and stretch more than a thinner tube because there is just morethere to do so. Because of this, each type tube has a certain amount of pressure that can beapplied to it before this becomes detramental to the strength of the tube. Once this pressurebecomes enough to start stretching and tearing the fibers of the tube, then the strength of the tubeis lost. Imagine a tube inside a sleeve, being pressed with a composition. If the tube has a thickwall, at a certain pressure, the paper starts to compress downward and outward. And whathappenes at this point, the tube starts to tear the paper fibers and the strength is lost. Take thesame tube made with the same paper with only 1/2 the wall thickness. Using the same pressure

8/9/2019 Rockets BP

28/33


- 28 -

exerted on the tube, there is less volume of paper to be compressed or to give when pressed. Theaffect on the walls of the tube is not as severe as it was with the thicker walled tube. The damageto the tube walls is less. Every tube has a certain amount of pressure that can be exerted to itbefore this damage occurs. And this damage will occur sooner to a thick wall tube than a thin walltube. I do use rocket tubes other than New England tubes but for purposes where the strength isno

rockets bp

Documents